The present invention relates to an apparatus and method for controlling performance dynamics in an electronic musical instrument or the like in response to player's gestures.
The present invention also relates to an apparatus and method for controlling a performance tempo in an automatic performance device in response to player's motions.
Automatic performance devices have been conventionally known which prestore in memory performance information on individual notes (note data) for melody and accompaniment performances, and automatically read out the prestored performance information at a given tempo to generate melody and accompaniment tones in accordance with the performance information. In such known automatic performance devices, the performance tempo is determined by a frequency of tempo clock pulses generated from a timer or the like, and the tempo clock frequency can be freely varied via a tempo setting switch or the like.
However, where the tempo is varied during a performance by operating the tempo setting switch or the like, it is very difficult to achieve fine tempo variations like those responsive to a player's gesture such as the player's handling or swinging of a baton, because the tempo variation depends solely on how the switch is operated (e.g., operated amount and velocity of the switch).
To provide a solution to the problem, an automatic performance device has recently been proposed, such as in U.S. Pat. No. 4,341,140, which is characterized by an accelerometer provided within a baton (conducting stick) that is handled or swung by the hand of a player or human operator. The device detects a maximal value of output signals from the accelerometer generated in response to the operator's swinging of the baton and controls a tempo and tone volume of an automatic performance at the time of the maximal value detection. By generating tone or advancing read address of sequence data at the time of the maximal value detection, the proposed automatic performance device can optionally control the performance tempo, and also control tone volume in accordance with the output values of the accelerometer so that performance dynamics (i.e., application of strength and weakness to sounds to give activeness to the entire performance) can be optionally controlled accordingly.
Namely, when the operator or conductor moves the baton strongly or rapidly, the accelerometer outputs a relatively great value and the performance dynamics are raised, so that the sound variation rate is increased to make the entire performance stronger; conversely, when the operator moves the baton weakly or slowly, the accelerometer outputs a smaller value and the performance dynamics are lowered, so that the sound variation rate is reduced to make the entire performance weaker.
In the automatic performance based on the conductor's actual swinging of the baton, the performance dynamics and tempo are controlled by various factors such as the conductor's beating, accelerating/decelerating and clicking actions and a shape of locus drawn by the tip of the baton linking the beating points. However, with the prior art automatic performance device where the performance dynamics are controlled in response to the operator's swinging of the baton, i.e., output signals from the accelerometer, strength, speed etc. of the operator's swinging motion undesirably tend to vary or become uneven depending on how skillful the operator is in conducting, feeling of the operator and contents (type or genre) of a music piece being performed. Such uneven strength, speed etc. would directly lead to unevenness in output values of the accelerometer, making it very difficult to execute a performance with dynamics as contemplated by the operator.
For example, if the operator swings the baton in a duple-time or quadruple-time vertical motion or a triple-time triangular-locus motion with no particular attention, the downward swinging movement (down-beat), in most cases, tends to be stronger and quicker than the upward swinging movement (up-beat) and lateral swinging movement of a second beat in a triple-time performance. Thus, even when the operator thinks that he or she is swinging at an uniform strength and speed, the output values of the accelerometer would undesirably vary in response to the unevenness in the swinging motion; that is, output values of the accelerometer caused by the downward swinging movement (down-beat) and hence the performance dynamics would become greater than those resulting from other swinging movements. This causes the performance dynamics to vary more or less in dependence on the operator's habit in making swinging motions.
Similarly, the performance tempo undesirably tends to vary or become uneven depending on how skillful the operator is in conducting, feeling of the operator and contents (type or genre) of a music piece being performed. Therefore, the performance tempo, i.e., timing to generate tone or advance read address of the sequence data, would differ from one operator to another. This presents a significant problem that a tempo as contemplated by the operator can not be obtained by merely generating tone or advancing read address of the sequence data at the time of detection of a maximal output value of the accelerometer.